1. Field of the Invention
The present invention relates to an uninterruptible power supply (UPS) and a method of power saving thereof; so that, compared to the prior art, the power consumption of the UPS is reduced.
2. Description of Related Art
In recent year, information technology has been developing quickly, various hardware apparatuses, such as a personal computer, a communication apparatus, and a workstation, are frequently used by every social class. Due to the fact that information may be a product of high commercial value, therefore many people utilizes all means to ensure the safety of information and normal operation of a computer system, and the demand of power quality for the computer system is becoming more and more restrictive. Because power electronic apparatuses are used more and more frequently, harmonic waves produced by power electronic apparatuses may result in that public power electronic apparatuses can not provide stable power, in addition natural disasters may also disrupt stable power supply, therefore an uninterruptible power supply has become an essential apparatus for a computer system or a communication system.
Refer to FIG. 1, an uninterruptible power supply 1 includes a battery 10, a charger 12, a converter 14, and a switch 16. While the public power AC is being provided normally, the public power AC is directly provided for a load 2 via the switch 16, the converter 14 at this point is on stand by, and the charger 12 charges the battery 10. While the public power AC fails and is not being provided normally, the converter 14 at this point is enabled, so that the battery 10 provides backup electric power AC′ for the load 2 via the converter 14 and the switch 16.
However, for the prior art, the uninterruptible power supply 1 is on stand by while the load 2 is disabled, so the uninterruptible power supply 1 still need electric power therefore causing a certain amount of power consumption.